[Skip to Content](https://www.sigmaaldrich.com#main-content) [](https://www.sigmaaldrich.com/US/en) Products Cart0 USEN Products [Login / Register](https://www.sigmaaldrich.com/oidc-sign-in) [Order Lookup](https://www.sigmaaldrich.com/US/en/order-lookup) [Quick Order](https://www.sigmaaldrich.com/US/en/quick-order) Cart0 [Home](https://www.sigmaaldrich.com/US/en)[Air Monitoring](https://www.sigmaaldrich.com/US/en/applications/environmental-testing-and-industrial-hygiene/air-testing)What is radiello® diffusive sampling? # What is radiello® diffusive sampling? In the mid 1990's, Dr. Vincenzo Cocheo, director of the Fondazione Salvatore Maugeri, Padova, Italy, in collaboration with the European Commission's Joint Research Center and other institutions, developed and patented a revolutionary diffusive/sampling design: Radial symmetry now registered trademarked as radiello (__Figure 1__). It consists of a radial diffusive body made of porous polypropylene in which a cartridge with adsorbent is positioned. The adsorbent bed is selected for application and can consist of a pure adsorbent material or a chemically coated support. Due to this symmetry analytes can access the adsorbent material throughout the 360° surrounding diffusuive barrier/body resulting in a significant higher uptake rate. By virtue of radial symmetry, the uptake rates with the same dimensions, radiello's are at least three times higher than for any axial diffusive sampler (__Figure 2__).  __Figure 1.__Radial Design of radiello  __Figure 2.__ Uptake/Sampling rates are higher for radial samplers than axial (e.g. Benzene @25°C <10mL/min vs. >70mL/min) Due to the tortuous nature of the diffusive path inside the micro-porous diffusive membrane, the uptake rate is not affected by wind or air currents. The stiffness of the diffusive wall and cartridge, together with the close tolerances characterizing all of the radiello® components, greatly reduces uptake rate variation. The uptake rates are not calculated, but are experimentally measured in a controlled atmosphere chamber over a wide range of concentration, temperature, relative humidity, air speed, and with and without interferences. The high capacity of the cartridge adsorbents provide a high capacity and minimal reverse diffusion.  __Figure 3.__Atmospheric Chamber Used to Measure Uptake Rates for radiello® Cartridge ## Features and Benefits of radiello® Samplers - The radiello design offers high uptake rates resulting in faster sampling - Greater adsorbent capacity offers minimal reverse diffusion and greater uptake rate consistency resulting in more reproducible results. - All uptake rates are precisely measured (not calculated) resulting in more precise measurements. - The water repellent diffusive body makes radiello amenable to bad weather - All cartridge adsorbents undergo a complex conditioning and QC procedure resulting cartridge background levels three times lower than instrument noise. - The combination of low detection limits, high uptake rates and high capacity allowing for sampling time ranges from 15 min. to 30 days (1 ppb – 1000 ppm). - Other benefits include, but are not limited to: - Predominately solvent/chemical desorption which does not require thermal desorption equipment - Amenable to thermal desorption & GC/MS with low interferences resulting in precise and very sensitive measurements - Touch and chemically inert making the sampler robust in use - Reusable hardware for more economic sampling - Available accessories (shelter) for ambient air analyses making radiello samplers amenable for a wide range of application areas ## Materials Sorry, an unexpected error has occurred Response not successful: Received status code 500 __Related Articles__ - [Radiello Sampler: Monitoring 1,3-Butadiene & Isoprene](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/analytical-chemistry/gas-chromatography/radiello-diffusive) - [Determination of Formaldehyde and Acetaldehyde in Air Using DNPH Cartridges and Automated On-Line Desorption Followed by HPLC](https://www.sigmaaldrich.com/US/en/technical-documents/protocol/environmental-testing-and-industrial-hygiene/air-testing/aldehydes-air-dnph) - [Efficient PAH Analysis (EU 15+1) using an Ascentis® Express PAH HPLC Column](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/analytical-chemistry/small-molecule-hplc/efficient-pah-analysis) - [PFAS Analysis Methods](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/analytical-chemistry/small-molecule-hplc/pfas-analysis-methods) - [PFAS Column Selection for LC and GC](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/analytical-chemistry/small-molecule-hplc/pfas-column-selection-for-lc-and-gc) - [PFAS Definition Classification Sources and Impact](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/analytical-chemistry/small-molecule-hplc/pfas-definition-classification-sources-and-impact) - [radiello™ Passive Sampler as a Tool for the Measurement of Atmospheric Ammonia Concentrations and Dry Deposition](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/environmental-testing-and-industrial-hygiene/air-testing/air-sampling-ammoniaradiello) - [Passive Air Sampling Tubes for US EPA Method 325](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/environmental-testing-and-industrial-hygiene/air-testing/air-sampling-method-325) - [View More](https://www.sigmaaldrich.com/US/en/search/facet-search?focus=sitecontent&term=facet-search) Top __Sign In To Continue__ To continue reading please sign in or create an account. 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